The present invention is directed to packaging components (e.g., a lid, a container, etc.) for packaging microelectronic devices (for example, semiconductor devices), packages (assemblies) formed using these packaging components (e.g., to form integrated microelectronic assemblies), and methods of forming the packaging components and packages. The present invention is especially directed to packaging components and packages formed utilizing such components, and methods for forming such components and such packages, which avoid damage and degradation of the microelectronic devices in such packages, due to hydrogen in the package. Thus, the present invention is directed to packaging components and packages, having hydrogen gettering structure, which avoid hydrogen degradation of packaged devices, particularly those devices having a low threshold hydrogen level in the hermetic (air-tightly sealed) package.
A problem experienced by semiconductor manufacturers, in connection with packaged semiconductor devices, is hydrogen degradation of the devices in hermetically sealed package. The hydrogen within the package can be generated from various parts of the package (for example, from housing materials, plated nickel layers, Eccosorb (a material used in semiconductor packages of, e.g., millimeter wave integrated circuits, to absorb electrical signals), epoxy adhesives, etc.).
This problem of hydrogen degradation is particularly acute with devices such as pseudomorphic high electron mobility transistors (PHEMTs) of monolithic millimeter wave integrated circuits (MMICs). Because these devices have thin nitride passivation layers, they are especially sensitive to hydrogen degradation, and a threshold hydrogen level in hermetic packages of these types of devices is very low, for example, about 100 ppm. However, such PHEMTs of MMICs are not the only types of devices particularly sensitive to hydrogen degradation; for example, MESFETs and indium phosphide high electron mobility transistors are other types of devices that are especially sensitive to hydrogen degradation and have very low threshold hydrogen levels in the hermetically-sealed package.
It has been proposed to mitigate the problem of hydrogen degradation, by baking out housing materials prior to populating the microelectronic device in the package and then sealing. While this has been successful in some instances, such technique to mitigate the problem of hydrogen degradation has not been sufficient, particularly with devices having a low hydrogen threshold level.
Another technique to overcome this problem of hydrogen degradation involves suspending inorganic hydrogen-absorbing material in silicone, in the device package. The inorganic hydrogen absorption material can be any of known metal oxide hydrogen getters. However, this technique has problems when utilized in packaging, e.g., microelectronic devices. For example, the material used undesirably takes up a large amount of moisture, requiring careful handling during the package sealing process. In addition, silicone may vaporize and contaminate electronic device and laser seal surfaces, and additional problems arise with the packaged device due to mobile impurity ions (for example, K.sup.+, Na.sup.+, C.sup.-, etc.) introduced due to this inorganic hydrogen absorption material in silicone in the package.